1. Field of the Invention
The present invention relates to an injection device for injecting a fluid product that includes a needle covering device.
2. Description of the Related Art
Injection devices are used for administering a fluid product such as a medicine, an infusion solution, or a contrast agent from a reservoir, e.g., an ampoule. An injection needle or cannula is used to inject the fluid product into human or animal tissue. When the fluid product in the reservoir is depleted, the reservoir should be able to be quickly and easily replaced.
For safety reasons and to prevent the fluid product from being unintentionally administered, the injection needle may be covered when not in use. However, the injection needle should be quickly and reliably accessible when the fluid product is to be administered. Moreover, since many users of injection devices have a psychological aversion (so-called “needle phobia”) to injection needles, it may be beneficial to obscure from view at least a portion of the injection needle.
Slip-on covering caps which can be removed or pushed together for covering needles are disclosed in WO 96/11026. Alternatively, retractable needle covering devices cover at least the end of the injection needle. The cover is retracted so that the injection needle can be injected into the tissue.
Such needle covering devices are disclosed in U.S. Pat. No. 4,804,372 and DE 40 13 769 A1. These injection devices are comparatively long. Thus, when attempting to place the injection needle at an angle to the surface of the tissue, the injection needle may bend and the needle and cover may draw relatively near, to the point where the injection needle jams in the needle cover. Moreover, replacing the fluid product reservoir is complicated, since the needle covering device has to be removed before the reservoir is replaced. The covering device must then be replaced afterwards on the new reservoir, which in the case of complicated injection devices, for example those comprising electronics, can lead to significant time loss and sources of danger.